Question

Cell reaction is spontaneous when

• A. $\Delta G^o$ is negative
• B. $\Delta G^o$ is positive
• C. $\Delta E_{\text{red}}^o$ is positive
• D. $\Delta E_{\text{red}}^o$ is negative

Answer 1

Answer: (A)

For spontaneous reaction value of $\Delta G^o$ is always negative.
Note: The free energy change $(\Delta G)$ of a photochemical reaction may not be negative.